The present invention relates to torque devices, and more particularly to a torque assembly that enables constant, controlled torque for a hinged object.
Torque hinges are well known in a variety of applications. In general, a torque hinge provides a degree of resistance throughout the range of motion of a hinged object. In automobiles, torque hinges are commonly used to control the movement of objects such as storage compartment lids, sun visors, grab handles, and movable armrests. Other common applications include hinged portions of electronic devices, such as laptop computers.
One common style of torque hinge is a spring torque hinge, which typically includes a torsion spring wound around a shaft. The ends of the torsion spring are fixed in position to compress the coiled spring about the shaft, creating a friction fit between the spring and the shaft that creates resistance through the shaft's range of motion. Another torque hinge style eliminates the spring, and includes a shaft having a coating made from urethane, Teflon or another compressive material that is press fit into a housing to form an interference fit between the coated shaft and the housing.
Unfortunately, conventional torque hinges of all styles suffer from disadvantages in that they tend to wear out over time, decreasing the amount of friction on the shaft and thus reducing the amount of resistance on the shaft to an undesirable amount. In the case of spring torque hinges, the springs tend to come uncoiled over a period of time, reducing their compression about the shaft. Other materials suffer from wear or deformation, which tends to reduce the friction between those materials and the shaft over time. Many torque hinge designs are incapable of meeting current heightened safety and quality standards in various industries.